Monthly Archives: October 2014

PRK (photorefractive keratectomy) was the first laser vision correction used to eliminate glasses and contact lenses. The first PRK was done in North America in the 1980’s and PRK has remained an excellent way to eliminate nearsightedness, farsightedness, and astigmatism.

PRK involves removing just the surface layer of cells on the surface of the cornea (the clear winshield-like structure on the front of the eye) and then reshaping the surface using the excimer laser. A contact lens is placed on the surface for three to five days as the surface cells grow back to cover the cornea. Most people are back to usual activities in 7 to 10 days.

LASIK (laser in situ keratomileusis) was developed in the 1990’s as a way to speed up the recovery from laser vision correction. Also called “Flap & Zap”, LASIK involves cutting a flap from the cornea, folding it back out of the way to reshape the surface underneath with the excimer laser, and then replacing the flap to it’s original position. This allows people to be back to usual activities within a day or two but does carry higher risks; the LASIK flap is more complicated to create, the flap can be shifted even months or weeks later, and the cornea is weakened more from the LASIK flap.

For over twenty-five years surgeons have preferred to use PRK for people with thin corneas or other factors that may make LASIK too risky. With the newer excimer lasers a customized wavefront laser pattern can be used. This custom wavefront treatment uses a map of the patients vision system to create an individualized laser treatment pattern – much like a fingerprint that is customized to each individual eye. Some surgeons believe that a customized treatment is more effective with PRK because the LASIK flap will cover up the finely customized wavefront treatment.

Many surgeons around the world are choosing PRK as their preferred way to do laser vision correction due to the excellent results and safety. Although the risks are low with LASIK, they are lower with PRK and most complications of PRK are easier to treat than a complicated LASIK flap.

For people who are looking for safe and effective laser vision correction the combination of PRK/Advanced Surface Ablation with customized wavefront laser treatment is an excellent choice.

If you have questions about laser vision correction or wish to book a complimentary evaluation with Dr. Anderson Penno, contact Western Laser Eye Associates.

Ebola is one of the least likely diseases that you might catch in North America, but it has raised awareness of the risks of infectious diseases.

The top 10 causes of death in high income countries like Canada and the US according the the World Health Organization WHO:

1. Coronary Heart Disease

2. Stroke

3. Lung and Other Respiratory Cancers

4. Lower Respiratory Infections

5. Chronic Obstructive Pulmonary Disease

6. Colon and Rectal Cancer

7. Alzheimer and Other Dementia

8. Diabetes

9. Breast Cancer

10. Stomach Cancer

HIV/AIDS, perinatal (deaths in childbirth), accidents, and malaria make the top ten in lower income countries.

According to the Huffington Post there are 5 more scarier infections to worry about. Rabies kills about 55,000 people in Africa every year and is one of the deadliest viruses. Hiv/AIDS has killed over 36 million people and can be treated but not cured. More than 600,000 people are killed worldwide by mosquito spread disease like malaria, dengue fever, yellow fever, and West Nile – every year. Rotavirus is a particular problem for children under the age of 5 in developing countries.

In the top 5 viral diseases scarier than Ebola is Influenza which kills between 3,000 and 49,000 in the US each year. Worldwide between 250,000 and 500,000 people die each year from influenza.

Ebola has been around for decades but has more recently become epidemic in some areas of Western Africa. There have been approximately 4,000 deaths so far from Ebola according the Centers for Disease Control and Prevention/ CDC.

You are more likely to become ill or die from the far more common influenza virus, but with any infectious disease there are common sense steps you can take to protect yourself:

1. Get vaccinated if a vaccine is available. Influenza vaccines are available with the latest strains every year and there may be an Ebola vaccine available in the future.

5. Don’t forget about common sense heart health including not smoking, exercise and watching your weight, and having proper screening for common diseases like colon cancer and breast cancer that are more likely to be treatable if found early.

Ebola is scary because it is new, but in developed countries sensible precautions are likely to prevent the devastating outbreaks that have been seen in African countries. Everyone can do their part to slow down the transmission of all infections by common sense measures like hand washing, covering your mouth when coughing or sneezing, and staying home when you are sick or feverish.

Ebola is one of the least likely diseases that you may catch in North American but it is a good reminder to take common sense steps to avoid both the rare Ebola and the more common Influenza.